Mr. Singh is appealing the ruling. Meanwhile, a number of influential reporters and writers are mounting a campaign called "Keep Libel Laws Out of Science" and are sending an open letter to Members of Parliament. The letter reads:

The law has no place in scientific disputes We the undersigned believe that it is inappropriate to use the English libel laws to silence critical discussion of medical practice and scientific evidence.

The British Chiropractic Association has sued Simon Singh for libel. The scientific community would have preferred that it had defended its position about chiropractic for various children's ailments through an open discussion of the peer reviewed medical literature or through debate in the mainstream media.

Singh holds that chiropractic treatments for asthma, ear infections and other infant conditions are not evidence-based. Where medical claims to cure or treat do not appear to be supported by evidence, we should be able to criticise assertions robustly and the public should have access to these views.

English libel law, though, can serve to punish this kind of scrutiny and can severely curtail the right to free speech on a matter of public interest. It is already widely recognised that the law is weighted heavily against writers: among other things, the costs are so high that few defendants can afford to make their case. The ease and success of bringing cases under the English law, including against overseas writers, has led to London being viewed as the "libel capital" of the world.

Freedom to criticise and question in strong terms and without malice is the cornerstone of scientific argument and debate, whether in peer-reviewed journals, on websites or in newspapers, which have a right of reply for complainants. However, the libel laws and cases such as BCA v Singh have a chilling effect, which deters scientists, journalists and science writers from engaging in important disputes about the evidential base supporting products and practices. The libel laws discourage argument and debate and merely encourage the use of the courts to silence critics.

The English law of libel has no place in scientific disputes about evidence; the BCA should discuss the evidence outside of a courtroom. Moreover, the BCA v Singh case shows a wider problem: we urgently need a full review of the way that English libel law affects discussions about scientific and medical evidence.

Among the early signers from the media and publishing are

David Aaronovitch Columnist, The Times and Author

Monica Ali Writer and Member, English PEN

Yasmin Alibhai-Brown Journalist and Columnist

Julian Baggini Journalist and Writer

Wendy Barnaby Editor, People and Society

Penelope Bennett Writer and Member, English PEN

David Bodanis Journalist and Author

Rosie Boycott Former Editor, The Independent and Independent on Sunday

Geoffrey Carr Science Editor, The Economist

Marcus Chown Author, Journalist and cosmology consultant to New Scientist

Duncan Campbell Journalist and Author

Dr Philip Campbell Editor-in-Chief, Nature

Nick Cohen Columnist, The Observer

Clive Cookson Science Editor, Financial Times

Amanda Craig Writer and Member, English PEN

Nick Davies Journalist and Author of Flat Earth News

Blain Fairman Writer and Member, English PEN

Kendrick Frazier Editor, Skeptical Inquirer

Martin Gardner Author, Former Scientific American columnist and prominent skeptic

James Gleick Science Writer and Journalist

Dr Ben Goldacre Writer, Broadcaster and Medical Doctor

David Hare Writer and Member, English PEN

Nigel Hawkes Director, Straight Statistics and Former Health Editor, The Times